ZERON 100 Welding Guide [Corrosion Resistant ... - Rolled Alloys

More documents

Recommendations

Info

ZERON ® 100 Welding Guidelines Contents Preparation for welding ZERON 100 ....................................................................................................................................................2 Welding Consumables........................................................................................................................................................................2 Typical Joint Configurations.................................................................................................................................................................2 Welding..........................................................................................................................................................................................3 Welding Procedure............................................................................................................................................................................4 Post Weld Cleaning...........................................................................................................................................................................6 Health and Safety.............................................................................................................................................................................6 Summary........................................................................................................................................................................................6 ZERON ® 100 Super Duplex Stainless Steel ZERON 100, invented and developed by RA Materials (formerly Weir Materials), was the first of the super duplex stainless steels. The unique chemical composition has been shown to be correctly balanced to offer the best combination of corrosion resistance and strength. The steel is tightly controlled from melting through manufacture to ensure a better performance than the same generic grade. ZERON 100 is available in all product forms, many from stock, with a proven track record through manufacture, fabrication, and successful service. When welding ZERON 100 super duplex stainless steel, there are several factors that must be considered. These guidelines highlight the main factors that must be taken into account. They relate particularly to welds to be used in the “as-welded” condition, made using all the common arc welding processes. The same principles apply if post weld heat treatment is being applied. The RA ® is a registered trademark of Rolled Alloys ZERON ® 100 is a registered trademark of RA Materials STT ® (Surface Tension Transfer ® ) are registered trademarks of Lincoln Electric DSP (Dual Sync PulseWelding)is a registered trademark of Dimetricks Inc. The data and information in this printed matter are believed to be reliable. However, this material is not intended as a substitute for competent professional engineering assistance which is a requisite to any specific application. Rolled Alloys makes no warranty and assumes no legal liability or responsibility for results to be obtained in any particular situation, and shall not be liable for any direct, indirect, special, or consequential damage therefrom. This material is subject to revision without prior notice. 1
Preparation For Welding ZERON 100 It is strongly recommended that a Welding Procedure Specification (WPS) and corresponding welding Procedure Qualification Record (PQR) be available prior to commencement of production welding. The WPS should be qualified to a higher level than the statutory requirements of the base codes such as ASME etc. and should include an ASTM G48 Method A corrosion test, a microstructural evaluation and ferrite determination in addition to the mechanical and non-destructive tests required. Welder qualification (WPQ) should also carry these extra requirements to show that the metallurgical quality of the weld area is satisfactory as well as the structural integrity for the codes. There should be considerable emphasis by the Welding Engineer on maintaining the qualified parameters throughout production welding. Handling and Storage of Parent Material All duplex stainless steels should be handled and stored under conditions which prevent contamination from other ferrous and nonferrous alloys. Stainless steel (or wood, plastic or other non-metallic material) protective covers should be used with storage racking, fork lift truck arms, overhead crane slings etc. Welding should be carried out in a contaminant free work area as recommended for other stainless steel fabrications. Only qualified duplex stainless steel should be used for temporary attachments at the corrosion side. A minimum number of temporary attachments should be employed. It is important that all metal in the welding area is dry and free of other contaminants, such as greases, to avoid hydrogen cracking when welding. Handling and Storage of Welding Consumables Welding consumables for ZERON 100 should be handled and stored in accordance with the manufacturer’s recommendations. In general, the consumables should be stored in an “electrode store” held at approximately 10°C (20°F) above ambient temperature and with a relative humidity below 60%. Opened packs of electrodes and flux should be baked in accordance with the manufacturer’s recommendations. Identification of Materials to be Welded Check against the welding procedure, specifications and drawings that the materials and welding consumables are correct and identified. Where it is necessary to mark materials using pens or paint markers, these must be free of chlorides, sulfides, halides and zinc. Welding Procedure Specification Check that an appropriate WPS and PQR are available, outlining the welding procedure to be followed. The procedure should be qualified in accordance with the recommendations of the latest issue of MDS 12804/21, or other similar specifications. Tooling Use only stainless steel grade cutting tools, grinding discs, grinding wheels, wire brushes and polishing wheels. Joint Preparation Welding bevels should preferably be prepared by cold methods. Where plasma cutting is used the process should be under water and at least 1 mm (0.04”) of material should be ground off to remove the heat affected zone. Recommended joint configurations for single sided welds are detailed in the next section. The recommended root gaps, root faces and joint angle are based on the need to: • Maximize production • Minimize parent metal dilution in the root • Control the heat input For this reason, control of the root gap is considered an important factor. Compound bevels must be balanced to ensure access while minimizing joint volume. Welding Consumables Two grades of welding consumables are available. ZERON 100 “M” grade has a composition matching that of the parent material and should generally be used for joints that are to be solution annealed. ZERON 100 “X” grade is overalloyed with nickel and is intended for joints that are to be put into service in the “as-welded” condition. Autogenous welding of square close butt preparations can only be used under specific circumstances and its use needs to be considered on a case by case basis. Advice on specific situations can be supplied on request. Typical Joint Configurations Manual Welding The joints detailed in Tables 1, 2 and 3 are for single sided manual welding with the GTAW or GMAW-STT process in the root. Other joints, for example two sided, are similar to those applied in general stainless steel practice. Table 1 - Typical Manual Welding Joint Configuration/Single Bevel Wall Thickness (t), mm (in) Included Angle (a), degree f g Root Gap (g), mm (in) t Root Face (f), mm (in) 2-3 (0.08-0.12) 70-90 2-3 (0.08-0.12) 0.5-1.5 (0.02- 0.06) > 4 (0.16) 70-80 2-3 (0.08-0.12) 0.5-1.5 (0.02- 0.06) 2
Page 1: WELDING GUIDELINES ZERON ® 100 UNS
Page 5 and 6: Back Purging When welding ZERON 100
Page 7 and 8: Joint Filling Using Submerged Arc (

ZERON 100 Welding Guide [Corrosion Resistant ... - Rolled Alloys

You also want an ePaper? Increase the reach of your titles

Delete template?

Save as template?